The present invention relates generally to the field of paper traps and more particularly is directed to a sheet material trap installed as part of a dust control system.
In the manufacture of fibrous, light-weight products, such as tissue paper, it is often necessary to control dust at the station of manufacture, both to assure proper quality control and also to provide adequate environmental safety conditions for the workers. Dust control systems including fans, ductwork, dust separators and necessary controls have been employed for this purpose. Experience has proven that large pieces of paper tissue and trimmed scrap in addition to the dust particles will frequently be exhausted into the dust control system at the manufacturing station. Adequate provisions must be built into the dust control ductwork to trap such large pieces of tissue paper or other sheet materials before the paper can reach the dust separator. Failure to remove the larger sheet materials can cause the dust separator to clog and thereby substantially eliminate all of the beneficial effects which would be expected from a properly functioning dust control system.
Prior workers in the art have addressed the problem of paper in a dust control duct by providing a paper trap which essentially comprised a plurality of inclined grid bars interiorly positioned within the exhaust duct to catch large pieces of tissue paper or other sheet materials to prevent them from being exhausted further downstream in the system. As the grid bars trapped more and more pieces of the sheet materials, the bars became clogged and the effective free interior duct area was thereby reduced. As more and more pieces of tissue paper became entrapped upon the grid bars, the efficiency of the dust control system was substantially reduced, thereby requiring periodic down time to permit an operator to open an access door located at the paper trap to manually remove all trapped paper tissue or other sheet-like materials from the grid bar. While the manual system of grid bar cleaning was effective to keep the system functioning, such a manual method of operation has proved to be quite expensive both due to the cost of the labor involved and more importantly, due to the down time of the equipment itself.
In certain applications, greater volumes of sheet materials, such as paper tissue are picked up at the work station and exhausted into the dust control system than were originally intended. Under such conditions, much more frequent manual cleaning of the paper trap was subsequently required. This has resulted in more frequent interruptions to the normal manufacturing operation and an annoyance to the machine operators who have found it to be a nuisance to have to continually return to the paper trap for manual removal of the trapped paper.